Method of interlocking coiled springs



Patented Dec. 13, 1932 PAT-sur ori-ICE wILLiaivr Lnwrs, or Urrea, New YORK- METHOD OF INTEBLOCKNG COIIfED SPRINGS Application -led July 15, 1929. SerialNo. 378,548.

This invention relates to a cruciform spring and method of making the same, the spring being pr-eferably composed of two similar coils usually crossing each other midway between their ends and interlaced at the crossing to hold them against relative movement.` Y

These springs are adapted to'be used more particularly as resilient ties or connections between Vthe upholstering springs of beds, davenports, chairs and other cushions, such v for example as are commonly used in motor Vehicles.

Each cruciform spring may constitute a unitary article of manufacture having theV opposite ends of each coil provided with suitable hoolr or loops for attachment to the upholstering springs or other anchorages whereby the upholstering springs are resili 9 Vently held in more or less parallel spaced relation without interfering with individual resiliency under local load or pressure.

In the manufacture of these. cruciform springs as heretofore practiced, the coils have been brought into intersecting and interlaced relation by screwing each endwise between the helices of the other transversely thereof until the ends of the coils beyond thel intersection are of substantially lengths.

That method, however, requires considerable time and frequently results in unequal projections of the ends of the coils beyond the crossing and consequent deflection or distortion of the ends of the coils and'upholster-ing springs to which they are attached.

The main object of the present invention is to enable the coil springs to be more expeditiously and accurately assembled than has heretofore been practiced by directly interlacing or interlocking the helices of the coils at their crossing.

Another object is to enable the intersecting I?, coils to be brought into substantially the sam-e i plane parallel with their axes so that when attached to the upper helices of the upholstering springs the upper surfaces of the cruequal ciform coils will lie in substantially the same plane as the corresponding ends of the upholstering springs and, when assembled in the form spring.

-Will be inclined at a lesser angle to said axis .within the space 2' so that-one or more cushion their upper surfaces will be disposed at substantially thesame plane as thecorresponding ends of the upholstering springs.

Other objects and uses relating to specific parts of the cushion springs will be brought out in the following description. i i

ln the drawing :-f y Y Fig. l is a fac-e view of one corner of ya spring cushion embodying the various fea tures of my invention. Figs. 2 and 3 are enlarged face views of one of the spring coils adapted to form the cruci- Figs. 4 and 5 are further enlarged face views of the intersecting portions of the cruciform coils showing the steps in the process of assembling the same,

' Figs. 6 and 7 are sectional views taken in the planes of lines G-6, Fig. 4, and lines 7-7, Fig. 5 respectively. 70

Fig. 8 is a sectional view taken in the plane of line 8-8, Fig. 5.

The cruciform'springs forming the subject matter of the present application are adapted to be used in connection with a system of uphostering springs -A- which are `supported at one end upon suitable bars I1- in uniformly spaced relation both longitudinally and transversely, the louter endhelices of the marginal springs -A- being connected by ties fc to a marginal vframe Each cruciform spring comprises a pair of similar coils 1 and #2# except that certain adjacent helices preferably midway be- 8? tween the ends of the coil -2- are spread apart to form intervening space -2- of about the same length asy the diameter of the coil 1*- to allow the latter to be seated in said space crosswise of the coil 2.

Under these conditions, the connecting helix -2- extending across one side of the said space will be somewhat elongated lengthwise of the axis of the coil -2- and than the remaining helices. y

In assembling the two coils, the intermee diate portion of the Coil -1- preferably midway between its ends is placed crosswise e upon the connecting helices of the coil -lmay rest upon the inner face of the helix -2- of the coil -2- whereupon the turning of the coil -2- in either direction about its axis through an arc of approximately 180 will cause the helix *2- to enter the space between adj acent helices of the coil `1 as shown in Figs. 5, 7 and 8.

This turning movement of the coil -2 relatively to the coil -Vl will also cause a part of the helix *24 to pass under one of the adjacent helices of the coil 1* and another part to pass over another adjacent helix ofthe same coil thus locking both coils l against relative lateral or endwise movement particularly when the ends of both coils are eld'against turning as for example when anchored to their respective upholstering springs as shown in Fig. l, and at the same time holding both coils in one and the same plane as distinguished fromthe usual endwise screwing method in which the intersecting portions are necessarily in different planes. Y

In other words in applicants cruciform spring, the axis of both coils at the'crossng are disposed in substantially the same plane and therefore if the coils are of uniform diameter, the corresponding outer faces of both coils will also be in substantially the same plane so that when the cruciform springs are assembled upon the upholstering springs to form a spring seat or cushion their upper surfaces will be substantially liat for receiving and supporting the fabric or other mattress. f

In practice, a spring-wire coil of uniform diameter may first be made of any desired length and by any well-known process, and then cut into suitable (preferably equal) lengths after which two lof the adjacent ihelices of one of the sections midway between the ends thereof are spread apart'at one side -to form an opening of about the same length as its diameter.

The other coil section may then be placed crosswise between the spread helices of the 4face section, preferably from the top downward so that the intersecting portions of the sections will lie in substantially the same plane.

Another section is then placed across in said opening with-its opposite ends projecting substantially, equal distances from the crossing and its intermediate portion resting helix -2 to bring the intersecting portions of both-sections in about the same plane after which the section `-2-V is turned about its axis about one-half jacent upholstering springs -A to hold said sections against relative turning movement.

In case any one of the sections should be impaired, the corresponding interlocked sections may be readily detached from the springs -A and the section -2- turned about one-half revolution to the position shown in Figure 8 to permit the section -lto be displaced from the opening -2-.

This direct interlocking` of the intersecting portions of the sections is not only simple and expeditious in greatly increasing the output of the cruciform springs and permitting the section -2- to be interlocked with the sections --l` and with the springs Aiafter the sections '--1- have been attached to the springs -A but also brings the intersecting` portions of the sections inv about the same plane as their remaining portions.

I do not wish, however, to limit myself to the spreading of the intermediate helices of either section before placing the sections in interlocking position for the reason that the intermediate portion of one section might be pressed between intermediate helices of the other section to produce the desired spreading operation without departing` from the spirit of the invention.

That I claim is:

The herein described method of interioclting two similar helical springs consisting in spreading adjacent helices of one spring apart a distance greater than the diameter of the other coil, placing said other coil crosswise between the spread helices of the rst coil and then turning the first coil about its axis relatively to the second coil to inter-- lock the helices of the crossing portions of the coils with each other against radial displacement and thereby to cause the crossing portions of both coils to lie in substantially the same plane.

In witness whereof hand this day of I have hereunto .set J une 1929. WILLIAM LEVIS.

revolution (more or less) 'to interlock the intersecting portions of bothV sections with each other against relative endwise or lateral movement.

The ends of the sections are then bent into hook-shape form and attached to the ad- 

